clarissa ward reports from the streets of osaka, japan. >> japan is fay puts for big screens and fancy gadgets but all those electronics require a lot of power and in japan, more so than many countries is incredibly reliant on nuclear energy as a source for their power. about 25% of the electricity here is generated by nuclear energy. there's been a debate for decades here about whether it's safe for a country that's as prone to earthquakes as japan, to be so reliant on nuclear power plants. and now, with a possible nuclear meltdown imminent, that debate is raging even more than before. it's friday, just afternoon in fukushima and white smoke, again, appears to be spewing from the reactors. earlier, the closest most detailed video yet of the damaged nuclear plant. taken from a helicopter, the video shows the shattered reactor 3 we destroyed by an explosion and also, number four, walls blown off and that's the greatest concern. this green structure entirely exposed. this is what it used to look like. and below it, more than 11,000 spent fuel rods. normally a pool of water keeps them coo